My buick wont start.

What is your question?

Its a 1990 buick century limited with a 3.3L V6. It starts for just a second and dies. We thought it was a fuel problem so we replaced the fuel pump, in line filter, And i just replaced the fuel pressure regulator. and it still doesn't start. we also put sea foam in the tank as well to clear any gunk. Pls Help.